Apparatus for making foraminous elements



July 7, 1936. CAMMEN I APPARATUS FOR MAKING FORAMINOUS ELEMENTS FiledDec. 10, 1932 ZSheetS-Shet 1 INVENTOR 'ATTORNEYS July 7, 1936. L. CAMMENAPPARATUS FOR MAKING FORAMINO US ELEMENTS Filed Dec. 10, 1932 2Sheets-Sheet 2 INVENTOR ATTORNEYS Patented July 7, 1936 UNITED STATES:

APPARATUS FOR MAKING FORAMINOUS ELEMENTS Leon Gammon, New York, N'. Y.,assign'or to Preston Davie, New York, N., Y. Application December 10,1932, Serial No. 646,732 15 Claims ((1153-13) This. invention relates toapparatus for making foraminous elements and has for its particularobject the provision of an improved apparatus for automatically" forminga foraminous element from a continuous thin strip of material.

The particular structure of the foraminous element and a method' ofmaking it are'described in mycopending application, Serial No 646,733,

fi led December 10,- 1932.

As pointed out in my aforementioned copending application, theforaminous element is constructed of a continuous thin strip of metal,suchas' copper, brass, or the like, of substantially 155 greater widththanthickness. The flat surfaces of the thin metal strip are provided atequally spaced intervals with a series of fine transverse grooves orknurling; grooved and ungrooved areas on one flat surface of thestripbeing staggered with respectto the corresponding areas on the other fiatsurface thereof. Thus the grooved areas on. one surface of the strip areoppositely disposed to the ungrooved areas of the. other surfacethereof,

etc. The ungrooved areas on each surface of the strip are alsoarrangedso as to overlap: hence, a short length of the strip, at regularintervals, is entirely ungrooved on either surface. 3

The alternately grooved and ungrooved strip is bent inzigzag formflatwise upon itself, the successive. bends: being. made in. oppositedirections at the uniformly spaced ungrooved. area intervals, so thatnone of the. grooves; are deformed in the bending operation and theformation of cracks at the bends is avoided :In this Way, uniform-1ydisposed and substantially identical iorarnina are formed between thecontiguous grooved and ungrooved surfaces of theadjacent strips.

This construction readily lends itself te the production of a foraminouselement structureessentially rectangular in shape. It may then beclamped: or otherwise mechanically secured 45 inany convenient mannerso: as to permanently retain: the contiguous strip layers: in propercontact and to permanently maintain the completed elementin rectangularform,

The. completed structure may be generally de- 50 scribed as a.foraminous element. having a substantial' but uniform thickness, andwherein a myriad of' uniform and substantially identical macroscopic (incontradistinction to microscopic-l foramina provide a myriad ofmacroscopic con- 55 tin-nous assages of substantially greater length thealternately spaced the greatest dimension of, normal cross; sectionthereof.

As to dimensions, the grooved portion of the strip should. be soconstructed as to provide in conjunction with the contiguous ungrooved,5: (smooth) surfaces of the strip, foramina of the order ofone-hundredth (0.01) of an inch in their greatest dimension of crosssection. The length of the foramina is largely determined by the widthof the strip, so-that a width should 1o be chosen of theorder of fourtimes or more the greatest dimension of cross section.

If the greatest dimension of cross section of the foram-ina. normal tothe length thereof is selected as five-thousandths (0.005) of an inch'lsor less,'the width of the strip should be selected so as to provide: apassage length of not'less than of the order of seven times the greatestdimension of cross section normalto the length thereof.

It the element structure is: to be employed for 2(} the purpose ofsurface tension dialysis, as generally described in my copendingapplication, Serial No. 638,329, filed October 18, 1932, the 'dimensionsof the foramina should be predetermined so that the regulated pressureto be ap- 25, plied to the commingled liquid masses bears a" definiterelation" both with respect to the surface tension of the liquid orliquids to be selectively recovered to the exclusion of otherscommingled therewith, and the dimensions as chosen.

If, however, the element is to be used merely as a permeable septum fora filtering operation, the dimensions of the-foramina may bepredetermined without regard to the surface tension of the filtrate andmay, therefore, be chosen so that they are of a suitable size torestrain the solid particles.

In accordance with the present invention, I provide an apparatus forautomatically carrying outnot'only the staggered grooving or knurling 0of the flat metal strip, but also for bendingit in the manner alreadydescribed. Like the disclosure of my aforementioned application, SerialNo. 646,733, filed December 10, 1932, I provide a pair of suitablespaced and driven cylindrical knurling rolls for grooving the surfacesof the strip in the-described manner, as hereinabove set forth. 7

The mechanism for automatically folding the grooved strip includesfeedand' tensioning rolls between which the grooved strip isintermittently advanced so as to be fed in timed relation to the foldingmechanism per se. The folding mechanism includes guides which supportand hold the strip during the time that oscillating-camactuated diesengage the strip at the points where the folds are to be made therein.The cam-actuated mechanism bends the strip flatwise at right angles inalternately opposite directions. The feed of the strip by the feed rollsis arrested during this period. Each right-angle folded portion of thestrip is then swung laterally over a stationary anvil by an oscillatingfinger and is engaged by a trigger hammer, the impact of which crimps orflattens the right-angle fold against the aforementioned stationaryanvil so that the strip is folded upon itself. Two sets of triggerhammers, oscillating fingers and stationaryanvils are provided to obtainthe necessary right and left or zigzag folding of the strip. The triggerhammers are released and retracted at the appropriately timed intervalsby cams. The strip, folded in this fashion, feeds through a guide chuteand may be stacked to the proper length to provide a foraminous elementof the required dimensions. The number of folds or layers of the foldedstrip determine the length of the finished element and are indicatedcontinuously on a dial.

For a more complete understanding of the apparatus of this invention,reference may be made to the following description thereof, consideredwith the accompanying drawings, in which Fig. 1 illustrates in enlargedperspective the toothed rolls for grooving spaced areas of each flatsurface of the metal strip stock;

Fig. 2 is a plan view of the strip-folding apparatus, a portion of whichis shown in horizontal section as seen along the line 22 of Fig. 3;

Fig. 3 is a vertical section though the apparatus as seen along the line33 of Fig. 2;

Fig. 4 illustrates the construction of the cam for controlling theintermittent feed of the strip;

Fig. 5 illustrates the shape of the cam for actuating the strip-foldingdies; and

Fig. 6 is an enlarged edge view of the completed foraminous element madeby the apparatus of this invention.

Referring to Fig. 1 of these drawings, numeral l0 designates the stripstock from which the foraminous element is to be made. The stockpreferably consists of a flat strip of soft metal, such as copper, brassor other suitable material, of a width sufficient to provide the desiredlength of passages, and of a thickness consistent with the requiredcross-sectional dimensions of the foramina of the finished element.

The strip stock I B may be drawn from a supply reel by or fed to a pairof grooving rolls l and l 2 fixed on respective shafts l3 and l4journaled in rotatable supports, not shown, and connected together andmaintained in proper angular relation by meshing spur gears l5 and I6fixed on shafts l3 and I4, respectively, one of which may be driven froma suitable source of power, not shown. The rolls l l and I 2 areappropriately spaced apart to frictionally accommodate'the strip stockIn, which feeds fiatwise between them as shown in Fig. 1.

The surfaces of the rolls I l and I2 are provided with a series ofradially projecting teeth I! of the proper size and shape to produce theforaminaforming groove ill of required dimensions in the oppositesurfaces of the strip stock 10. These teeth I! extend parallel to theaxes of the corresponding rolls and transversely to the strip stock l8,and occupy slightly less than one-half the periphery of each roll,leaving an ungrooved surface I9 on each roll which, accordingly,occupies slightly more than one-half of the periphery thereof. Also, thegrooved areas of the rolls are displaced angularly about with respect toeach other, as shown in Fig. 1, and are maintained in this relationshipby gears l5 and Hi.

When the strip stock l0 feeds between the rolls constructed and arrangedin this way, the teeth ll of the rolls impress the grooves I8 in theopposite surfaces of the strip stock ID to form the opposite toothedareas 20. Because of the aforementioned angular displacement of thetoothed. areas of rolls II and I2, the grooved areas 20 on oppositesides of the strip are staggered with respect to each other lengthwiseof the strip, so that the area 2| of the surface of the finished stripopposite each grooved area 28 remains flat and smooth, having beenengaged by the ungrooved surface IQ of the corresponding roll. Becausethe toothed areas of each roll I! and I2 occupy less than one-half ofthe periphery thereof, a short length 22 of the strip remains ungroovedupon either surface. It is at the centers of these spaced ungroovedareas 22 that the strip I0 is folded, in order that none of the groovesl8 will be distorted during the folding operation to produce foramina ofnon-uniform dimensions. Furthermore, the ungrooved folding areas 22 arestronger than the grooved portions of the strip, both because they arethicker and because they are not subject to the hardening which resultsfrom the deformation of the metal during the grooving process and whichmakes the metal brittle and likely to crack when folded.

The grooved strip IB is then fed to the folding apparatus, shown in planin Fig. 2, at the proper timing to secure the required cooperationbetween the folding areas 22 of the strip Ill and the folding devices tobe described, which are adjusted to secure this cooperation.

The strip folding apparatus illustrated in plan in Figure 2, includes abase 23 upon which is mounted the horizontal shaft 24 journaled inbearings 25 and fitted with the driving pulley 26 connected by a belt toa suitable source of power, not shown. A bevel gear 21 fixed on shaft 24meshes with and drives bevel gear 28 mounted on .a horizontal crossshaft 29 journaled in bearings 30 mounted on the base 23. A bevel gear3! is secured to cross shaft 29 and drives bevel gear 32 secured to afeed roll 33 journaled on a short vertical shaft 34 suitably securedupon the base 23. An undriven second feedroll 35 cooperates with feedroll 33 and is journaled upon an arm 36 pivoted at one end on pivot pin31 secured to the base 23.

A link 38 is pivoted in the free end of the arm 36 and is slidabletransversely of shaft 24, which projects through a guide slot 39therein, as illustrated in Figure 3. The free end of link 38 carries aroller 40 which engages the edge of disc cam 4| secured on shaft 24.This cam is illustrated in detail in Figure 4 and comprises twosuperimposed discs 42 and 43, the latter being keyed on shaft 24 and theformer being secured thereto independently of the shaft 24. The disc 42is secured to disc 43 by screws A l which extend through arcuate slots45 in disc 42, whereby the latter may be adjusted angularly with respectto disc 42.

The profiles of the cam discs 42 and 43 cooperate to produce a movementof the link 30 to the left as seen in Figures 2 and 3, and the length oftime that the link 38 is held in this position is determined by theangular relation of discs 42 and 43. For example, by adjusting them sothat their profiles are moved toward each other, the resultant decreasein the length of their combined profiles causes a retraction of shorterduration," and vice versa. Accordingly, the adjustment of cam 4|determines the lengths of the periods of engagement and disengagement offeed rolls 33 and 35 with the strip stock which is accordingly fedintermittently.

A coil spring 46 is interposed between arm 36 and an adjusting screw 41threaded through an abutment 48 on base 23, and normally urges feed roll35 toward feed roll 33 during the dwell period of cam 4|, so that thestrip It! is driven by the feed rolls. The pressure of the feed rolls onstrip ID may be varied by adjusting the tension of spring 46 by means ofthe adjusting screw 41.

When cam 4| retracts arm 36 and disengages roll 35 from roll 33, againstthe pressure of spring 7 46, the feed of the strip I0 is arrested. Theadjustment of the cam 4| is made according to the lengths of the groovedareas 20 on the strip If! so that the strip is advanced a stepsubstantially equal in length to the grooved area 23 plus the length ofthe folding area 22, and the feed of the strip is timed so that theareas 22 are properly positioned for folding during the dwell period ofcam 4|. In this way, the machine may accommodate strip stock which isvariously grooved for making elements of different dimensions.

In order to prevent overrunning of the strip Ill and consequent bucklingand bending thereof during its intermittent feed and to tension it sothat it will feed evenly, a pair of tensioning rolls 49 and 5|] areplaced ahead of the feed rolls 33 and 35. Roll 49 is journaled on avertical pin 5| mounted in the base 23, while roll 51! is self-adjustingand is journaled upon an arm 52, which is pivoted at one end on a pin 53mounted on base 23 and which is urged toward roll 49 by a coil spring 54interposed between its free end and a screw 55 adjustably threaded in anabutment 56 mounted on base 23. The degree of tension which the rolls 49and 5!) apply to the strip I0 may be varied by adjusting the screw 55.

The strip I3 is fed by feed rolls 33 and 35 between a pair of guides 51and 58, the lower ends of which are squared to serve as anvils overwhich the strip Ill is bent at a right angle. Positioned to engage thatportion of the strip which projects beyond the ends of guides 51 and 58are two dies 59 and 59 which project from a die plate 3| slidablymounted in a guide 62 on base 23.

Connected to the die plate 6| is a link 63 which is slotted so as to beguided longitudinally on the shaft 64 which is journaled in bearings 65mounted on base 23 and which is driven by a bevel gear 66 mounted on theend of a horizontal cross shaft 29 and meshing with a bevel gear 61secured on shaft 64. Link 63 is provided with a pin 38 which projectsinto the groove 69 of cam 19 keyed on shaft 64 so as to rotatetherewith.

The groove 690i cam 19 is shaped as illustrated in Figure 5 and servesto oscillate die plate 6| so that dies 59 and 63 alternately engage thestrip to bend it at right angles in alternately opposite directions overthe anvil surfaces of guides 51 and 55. Accordingly, as cam 16 moves dieplate 6| to the right, as seen in Figures 2 and 3, die 59 engages stripI0 and bends it at right angles over the anvil surface of guide 51 withwhich die 59 cooperates. As the cam 10 moves die plate 6| to the left,as seen in Figures 2 and 3, die 66) engages strip l0 and bends it atright angles to the left over the anvil surface of guide 53. The feed ofthe strip by rolls 33 and 35 is so timed by cam 4| that the right anglebends are made therein at the folding areas 22, while the movementsofcams 4| and 15 are so timed with respect to each other that the formerdisengages feed roll 35 from strip II] to stop the feed of the latter atthe time that cam 13 advances die plate 6| to bend the strip II] atright angles in the manner described.

The bent strip I3 is swung laterally in opposite directions by theaction of dies 59 and 60 so that the bent portions thereof approach thesurfaces of stationary anvils 1! and 12, which are located adjacent thedies 59 and 69 respectively when the latter are in their retractedpositions as is indicated in Figures 2 and 3. Anvils 1| and 12 arerigidly secured to the base 23.

As illustrated in Figure 3 a frame 13' extends vertically from the base23 and on this frame is 1 journaled a spur gear 14 which is driven byspur gear 15 secured on shaft 64. Spur gear 14 meshes with and drivesspur gear 16 journaled on frame 13 and in turn drives a spur gear 11 oflike dimensions also journaled on frame 13. An idler gear 18 journaledon frame 13 is driven by gear 15 and in turn drives gear 19 which driveslike gear 86, all journaled on frame 13. Pivoted eccentrically on gears15 and 19 is a link til, the lower end of which terminates in a finger82, which is located in proximity to the strip H), as is indicated inFigures: 2 and 3. Since gears 16 and 19 are of the same size and rotatein the same direction the finger 82 thereof describes an arc. A similarlink 83 having the finger B4 is' pivoted eccentrically on like gears 11and and describes an arc in proximity to folded strip Ill but in adirection opposite to the are described by finger 82.

The timing of the mechanism just described is such that finger 82 enagesthe projecting folded portion of strip H) which lies adjacent the anvil12 and places it upon the latter, while finger 84 places the foldedportion of strip 10 on anvil 1|, the fingers 82 and 84 actingalternately so as to move in right and left directions in accordancewith the right and left bends formed in the strip N] by the dies 59 and59 in the manner described.

As finger 82 lays the bent portion of strip ||l upon anvil 12 a trigg rhammer 85, slidably mounted on a guide 86, is released by cam 81 so thatits spring 88 advances it abruptly into. engagement with the stripoverlying anvil 12. The impact of the trigger hammer 85 accordinglyfiattens or crimps the right angle bend of the strip, as is illustratedin Figure 2. The cam 31 is keyed on shaft 64 and is a crown cam whichcooperates with hook 89 on trigger hammer 85 so as to normally hold thelatter in retracted position against the pressure of spring 88. Cam 61is provided with a notch 99 which, as the cam 81 rotates, disengageshook 89 of trigger hammer 35 so that spring 88'advances the triggerhammer 35 against anvil 12 in the manner described.

Upon further rotation of cam 81 the latter re-engages hook 89 of triggerhammer S5 to slowly retract it along guide 36 and recompress spring 83.This retracted condition of the trigger hammer is illustrated on theleft-hand side of 6 Figure 2 where a similar hammer mechanism includestrigger hammer 9|, crown cam 92 and spring 93. Cams 31 and 92 aredisplaced angularly with respect to each other so that they operatealternately in synchronism with fingers 82 and 34. Accordingly, asfinger 84 lays the right angle fold of strip 15 upon anvil 1| cam 92releases trigger hammer 91 so that the latter flattens or crimps thestrip H) against anvil 1|. 7 7

As the strip is crimped in the manner described it is advanced through achute 95 formed between the guides 86, and the number of crimps, whichcorrespond to the number of layers of the completed element, areindicated on a stationary dial 96 by a pointer 9'17 rotated by the shaft64. In this way the length of the finished element can be determinedsince it depends upon the number of superimposed layers indicated in thedail 96.

The finished element is shown in enlarged form in Figure 6. It will benoted that the folds thereof, having been made in the ungrooved areas22, do not cause any distortion of the foramina 98 which are formedbetween the contiguous grooved and ungrooved surfaces of the successivelayers of the element. Also, since the folds are made in the thickerareas 22 of the strip they are stronger and serve to hold the adjacentlayers of the element in contiguity. Furthermore, the areas 22 where thefolds are made remain malleable as they are not affected by thehardening resulting from the deformation of the metal by the rollingprocess and therefore do not crack during the crimping process as wouldlikely be the case if the bends were made in the thinner and hardenedgrooved portions of the strip.

The operation of the machine of this invention will be readilyunderstood from the foregoing and it may be synchronized with thegrooving apparatus illustrated in Figure 1 so that both machines may beoperated together as a unit, but either machine may be operatedindependently and the strip prepared by the grooving machine may be fedin properly timed relation to the folding devices of the crimpingmachine illustrated in Figure 2.

While a preferred embodiment of the apparatus of this invention isillustrated and described herein, it is to be understood that theinvention is not limited thereby but is susceptible to vari ous changesin form and detail within its scope as defined by the claims.

I claim:

1. In apparatus for folding strip material, the combination of means forfeeding the strip material intermittently, means for partially foldingthe strip material at spaced points in alternately opposite directionsduring the dwell periods of the feeding means, and means operativeduring successive dwell periods of the feeding means for folding thestrip material upon itself at the partially folded portions thereof andadapted to engage only that portion of the material near the said folds.

2. In apparatus for folding strip material, the combination of means forfeeding the strip material intermittently, folding devices in the pathof movement of the strip material timed with the feeding means forpartially folding the strip material at spaced points in alternatelyopposite directions during the dwell periods in the movement thereof,and second folding devices in the path of movement of the strip materialfor folding it fiatwise upon itself at the partially folded portionsduring successive dwell periods in the movement thereof, said secondfolding devices being adapted to engage only that portion of thematerial near the said folds.

3. In apparatus for folding strip material, the combination ofoscillating die means, an anvil with which the means cooperates, meansfor feeding the strip material to the anvil for partial folding atspaced points in alternately opposite directions by the die means, andmeans adapted to engage only that portion of the material near the foldsfor folding the strip material upon itself at the intially foldedportions thereof.

4. In apparatus for folding strip material, the combination of means forfeeding the strip material, oscillating folding devices in the path ofmovement of the material for partially folding the material at spacedpoints in alternately opposite directions, and second oscillatingfolding devices timed with the first folding devices for folding thestrip material fiatwise upon itself at the successive partially foldedportions thereof and adapted to engage only that portion of the materialnear the said folds.

5. In apparatus for folding strip material, the combination of a meansfor feeding the strip material intermittently, folding devices timedwith the feeding means for folding the strip material at an angle atspaced points in alternately opposite directions during the dwellperiods in the movement thereof, and second folding devices timed withthe feeding means and the first folding devices for engaging only thatportion of the material near the angle folds thereof and folding it inalternately opposite directions flatwise upon itself to form an elementof substantially zig-zag shape.

6. In apparatus for folding strip material having spaced transverselygrooved areas on opposite flat surfaces staggered longitudinally withrespect to each other, the combination of means for feeding the stripmaterial, folding devices in the path of the material timed to partiallyfold the strip transversely in alternately opposite directions at spacedpoints between the grooved and ungrooved areas thereof, and secondfolding devices timed with the first folding devices for folding thematerial fiatwise upon itself at the successive partially foldedportions thereof to form a zig-zag element in which the contiguousgrooved and ungrooved areas form a plurality of foramina extendingthrough the element.

7. In apparatus for folding strip material, the combination of means forfeeding the strip material, folding devices in the path of the materialtimed to partially fold the strip transversely in alternately oppositedirections at spaced points along the length thereof, and second foldingdevices for folding the material flatwise upon itself at the successivepartially folded portions thereof, said second folding devices engagingonly that portion of the material near the said folds.

8. In apparatus for folding strip material, the combination ofoscillating die means, an anvil with which the means cooperates, meansfor feed ing the strip material to the anvil for partial folding atspaced points in alternately opposite directions by the die means, asecond anvil cooperating with the partially folded portions of thestrip, and second die means cooperating with the second anvil forfolding the strip material upon itself at the initially folded portionsthereof and adapted to engage only that portion of the material near thesaid folds.

9. In apparatus for folding strip material, the combination of a meansfor feeding the strip material intermittently, an anvil and cooperatingdie means timed with the feeding means for folding the strip material atan angle at spaced points in alternately opposite directions during thedwell periods in the movement thereof, and a second anvil and secondcooperating die means timed with the feeding means and first die meansfor engaging the material at the angle folds thereof and folding it inalternately opposite directions flatwise upon itself to form an elementof substantially zigzag shape.

10. In apparatus for folding strip material at spaced points along itslength, the combination of means for feeding the strip material, foldingdevices in the path of the strip material for engaging only that portionof the material near the said spaced points and partially folding thestrip material upon itself, and second folding devices for folding thematerial flatwise upon itself at the successive partially foldedportions thereof and engaging only that portion of the material near thesaid folds.

11. In apparatus for folding strip material, the combination of meansfor feeding the strip material, folding devices in the path of thematerial for partially folding the strip transversely in alternatelyopposite directions at spaced points. along the length thereof, and ananvil and cooperating die means for completely folding the material uponitself at the partially folded portions thereof, said die means beingadapted to deliver hammer-like blows to the folds placed upon the anvil.

12. In apparatus for folding strip material, the combination ofoscillating die means, an anvil with which the means cooperates, asecond anvil, a second die means cooperating therewith, and means forfeeding the strip material across the first anvil for partial folding bythe first die means and across the second anvil for complete foldingupon itself by the second die means at the partially folded portionsthereof, said second die means adapted to engage only that portion ofthe material near the said folds.

13. In apparatus for folding strip material, the combination of meansfor feeding the strip material, folding devices in the path of thematerial for partially folding the strip transversely in alternatelyopposite directions at spaced points along the length thereof, and ananvil and cooperating die means for folding the material flatwise uponitself at the successive partially folded portions thereof, said anviland die means engaging each partially folded portion separately andforcibly folding the material on each side of the fold together.

14. In apparatus for folding strip material, the combination of meansfor feeding the strip material, folding devices in the path of thematerial for partially folding the strip transversely in alternatelyopposite directions at spaced points along the length thereof, and ananvil and cooperating die means for folding the material flatwise uponitself at the successive partially folded portions thereof, said diemeans being adapted to deliver hammer-like blows to the folds placedupon the anvil, said folds being engaged separately by the anvil and diemeans which forcibly foldthe material on each side of the fold together.

15. In apparatus for folding strip material, the combination of meansfor feeding the strip material intermittently, an anvil and oscillatingdie means cooperating therewith positioned in the path of movement ofthe stripmaterial for partially folding the strip transversely inalternately opposite directions at spaced points along the lengththereof, said oscillating die means being timed to fold the stripmaterial during the dwell periods in the movement thereof, and a secondanvil and second die means cooperating therewith for folding thematerial flatwise upon itself at the successive partially foldedportions thereof, said second die means being adapted to deliverhammer-like blows tothe folds placed upon said sec- 0nd anvil andengaging each fold separately and only that portion of the stripmaterial near the said fold.

LEON CAMlVIEN.

